G10-CR
Grade
ASTM D709
Specify for superconducting-magnet and LHe/LN2 hardware: controlled resin system and lay-up qualified down to 4 K.
Values for the G10-CR condition
Other G10 grades and fills
G10 is listed in 4 conditions; see the grade overview at G10.
- FR4
- FR5
- Epoxy Matrix
- G10-CR
Compare all 4 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
flame-retardant (brominated) glass/epoxy, UL 94 V-0 | Pick when a UL 94 V-0 rating or PCB-compatible laminate is required; mechanical properties are essentially G10-like. | — | 300 | 1.7 | 110 HRM |
flame-retardant high-temperature glass/epoxy (G11 + V-0) | Choose for hot electrical apparatus that must also meet UL 94 V-0. | — | 300 | 1.6 | 112 HRM |
Epoxy MatrixDefault standard G-10 continuous-filament glass cloth / epoxy laminate | Default choice for structural/insulating machined parts where flame rating is not required and service stays below ~130 °C. | — | 310 | 1.8 | 110 HRM |
G10-CRThis page cryogenic-grade glass/epoxy laminate | Specify for superconducting-magnet and LHe/LN2 hardware: controlled resin system and lay-up qualified down to 4 K. | — | 415 | 1.9 | 110 HRM |
What is G10-CR?
G10-CR is G10 in the G10-CR grade — specify for superconducting-magnet and LHe/LN2 hardware: controlled resin system and lay-up qualified down to 4 K. G10-CR has a tensile strength of 415 MPa (60.2 ksi), stronger than 65% of composite grades. Elongation at break is 1.9% and the elastic modulus is 28 GPa (4.06 Msi). G10-CR has a density of 1.8 g/cm³ (0.065 lb/in³), heavier than 59% of composite grades. Its glass-transition temperature is 120°C (248 °F). Epoxy Matrix is the default condition FabDigit quotes; G10-CR is available on request or by drawing note.
Limitations
- Hard to polish — 25/100, worse than 76% of composite grades
G10-CR properties
Typical room-temperature values for G10-CR; 19 are specific to this condition. Other listed values are G10 reference data and may not represent this condition. Bars are the position among composite grades.
Physical4
G10-CR has a density of 1.8 g/cm³ (0.065 lb/in³), heavier than 59% of composite grades. Its glass-transition temperature is 120°C (248 °F).
Mechanical13
G10-CR has a tensile strength of 415 MPa (60.2 ksi), stronger than 65% of composite grades. Elongation at break is 1.9% and the elastic modulus is 28 GPa (4.06 Msi).
Thermal8
G10-CR is rated for continuous service to 130°C (266 °F). It conducts heat at 0.3 W/m·K (0.173 BTU/hr·ft·°F), worse than 63% of composite grades. Thermal expansion is 14 µm/m·K (7.78 µin/in·°F).
Electrical7
G10-CR is an electrical insulator with a dielectric strength of 20 kV/mm (508 V/mil) and a resistivity of 1×10¹² Ω·m.
Chemical & Environmental3
Corrosion resistance is excellent (85/100), better than 65% of composite grades. UV resistance is fair.
Sustainability4
Producing a kilogram of G10-CR takes about 110 MJ of energy and emits 7 kg of CO₂ — less than 60% of composite grades. Typical recycled content is 0%.
Manufacturability4
G10-CR's machinability is fair (45/100, better than 63% of composite grades); weldability not recommended (0/100); formability not recommended (0/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with G10-CR
Is G10 easy to machine?
Very abrasive — use sharp carbide or PCD/diamond tooling, high speed, low feed, climb-mill and back the exit side to prevent delamination; dust extraction and respiratory protection are mandatory.
Can G10 be welded?
Not weldable (thermoset); join by bonding with epoxy/acrylic structural adhesives or by bolting with washers to spread load.
Can G10 be formed, bent or molded?
Supplied fully cured; cannot be thermoformed or post-formed — parts are produced by cutting, milling, drilling, waterjet or laser (laser leaves charring).
What surface finishes work on G10?
Sanding/sealing with epoxy or polyurethane topcoat improves moisture and UV performance; deburr holes and seal cut edges to limit wicking; no plating without special activation.
G10 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| E-glass woven clothcontinuous-filament glass fabric (e.g. 7628/2116 style) | 50 – 65 | 58 |
| epoxy resin (DGEBA + hardener)non-flame-retarded for G10; brominated for FR-4 | ≥ 35 (balance) | — |
G10-CR — frequently asked
What is G10-CR used for?
G10-CR is typically used for electrical insulators and standoffs, knife handles and scales, transformer and coil spacers, switchgear barriers and terminal strips, cryogenic structural supports (G10-CR) and machine guards and non-conductive fixture plates. In short: premium electrical glass laminate.
What is the tensile strength of G10-CR?
G10-CR has a typical tensile strength of 415 MPa (60.2 ksi) — stronger than 65% of composite grades. Strength varies by condition: see the 4 listed tempers.
Is G10-CR easy to machine?
Reasonably — machinability is rated fair (45/100, better than 63% of composite grades). Very abrasive — use sharp carbide or PCD/diamond tooling, high speed, low feed, climb-mill and back the exit side to prevent delamination; dust extraction and respiratory protection are mandatory.
Can G10-CR be welded?
Not readily — weldability is rated not recommended (0/100). Not weldable (thermoset); join by bonding with epoxy/acrylic structural adhesives or by bolting with washers to spread load.
What surface finishes work on G10-CR?
Sanding/sealing with epoxy or polyurethane topcoat improves moisture and UV performance; deburr holes and seal cut edges to limit wicking; no plating without special activation.
Can G10-CR be formed, bent or molded?
Supplied fully cured; cannot be thermoformed or post-formed — parts are produced by cutting, milling, drilling, waterjet or laser (laser leaves charring).
What is the maximum service temperature of G10-CR?
G10-CR is rated for continuous use to about 130°C (266 °F), and briefly to 180°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in G10-CR?
Yes — G10-CR is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- NEMA LI 1 — Industrial Laminated Thermosetting Products — NEMA (1998)
- MIL-I-24768/2 (GEE) Plastic Sheet, Laminated, Glass Cloth, Epoxy — U.S. DoD (1994)
- Garolite G10/FR4 laminate datasheets — Professional Plastics / Current Inc. (2023)
- Handbook on Materials for Superconducting Machinery (G-10CR data) — NIST/Battelle (1977)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.